Houghton Mifflin Company. (2002). Houghton Mifflin mathematics. Houghton Mifflin.
Chicago-viite (17. p.)Houghton Mifflin Company. Houghton Mifflin Mathematics. Boston: Houghton Mifflin, 2002.
MLA-viite (8. p.)Houghton Mifflin Company. Houghton Mifflin Mathematics. Houghton Mifflin, 2002.
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